Jumbo Frames - how to get it running on Windows XP?

[frankomat]

Hi all,

sorry if I put this in the wrong section, feel free to move it, but I hope you could help me here.

I have a gigabit network running with 2 NAS (1 Linkstation Pro, 1 Linkstation Live) and 2 Windows XP PCs, both with Marvell Yukon Gigabit NIC on board.

As Switches I have a Netgear GS608 (Rev2) and a Linksys SLM2008, both support up to 9k Jumbo Frames.

For toubleshooting only one of the switches is connected to the setup.

Now the Jumbo Frames story:

When I set both Linkstation to Jumbo Frames (4k or 7k for example) I can see that packets > 1514 are going fine over to the other Linkstation. (ping test with larger packets works fine)
Write transfer from NAS to NAS via FTP is 40% higher than without Jumbo Frames.

=> My Switch is working with Jumbo Frames (even a friend double checked my switch in his network which also runs under Jumbo Frames, but with Macs) and works fine with the Linkstations running with Jumbo Frames.

Setting Jumbo Frames in the Windows XP PCs NIC properties to 4k or 9k Whireshark tells me in the interface details the MTU size is 4k, 9k according to the settings I did.

Anyhow, when I try to do a ping with a greater packet (ping -f -l 2000 <NAS-IP-or-other-PCs-IP>) it results in the message that the packet cannot be send as the DF-Flag is set.
Snooping the traffic with Whireshark I do not see any (TCP) packets passing over to the remote NAS/PC. The ARP packets back and forth for revealing the MAC address of the destination acoording to the called IP work fine.

Transferring files from the NAS to PC (or vice versa) I see that all TCP packets have 1514 byte size, so nothing about the expected Jumbo Frames.

Is there an additional setting I have to make in Win XP except for the one in the NIC properties?
I tries some changes in the registry, but none worked so far, so I rolled them back.

I use Comodo Firewall as the personal firewall. Also disabled it for testing. => no change.

I am quite frustrated ... do you have any ideas?

Thanks,
Frankomat

 

[thiggins]

You shouldn't have to do anything special in XP to enable jumbo frames. I would check for an updated Ethernet NIC driver.

 

[frankomat]

Thanks, for the tip, Tim.

I just saw the drivers were from late 2007, I bought the mainboard (Asus P5Q-E) Dec. 2008, so the driver disk was older.

Anyhow, I just upgraded to the latest drivers from the Marvell website for the NIC (88E8056), but the symptom stays the same.

Cheers,
Frank

 

[00Roush]

On my Vista machine that same Marvell NIC only has 1514, 4088, or 9014 bytes as options. No 7k option. Same goes for my Win XP Pro server that has two Marvell NICs onboard. Are you using the driver to set the frame sizes or some other software?

00Roush

 

[frankomat]

Oh,sorry. Yes, you are right. I mixed up the 7k setting I can do on my Linkstations in my first post. (corrected the post now)
On both PCs I use the settings in the drivers advanved properties which allow 1514, 4088 and 9014.

 

[00Roush]

Oh,sorry. Yes, you are right. I mixed up the 7k setting I can do on my Linkstations in my first post. (corrected the post now)
On both PCs I use the settings in the drivers advanved properties which allow 1514, 4088 and 9014.

So the Linkstation can only do 4k and 7k? If that is true the 4k one would probably be the only size you could use as the Marvell cards don't support the 7k size.

Not sure if you already have but you might restart the Windows computer after you make the jumbo frame change to ensure it takes effect.

00Roush

 

[frankomat]

Hi,
I don't think that the Linkstation Jumbo Frames setting is the issue because I am also not able to use Jumbo Frames between both PCs with the Marvell NICs and the same frame settings.

And as I am not able to use Jumbo Frames even if I set the Linkstation to the 4k size.
(In fact the Linkstation supports also 9694 Bytes, but that size is too big for the switch [9014 max])

I mentioned the Linkstations only to point out that the "rest of the network" (NASes, Switch) are able to run with Jumbo Frames.

Yes I restarted the PCs in case the JF setting only takes effect then... no change.

So in summary some of my tests regarding JF:
1) Linkstation1 (4k JF) --> Switch --> Linkstation2 (4k JF) => OK

2) PC1 (4k JF) --> Switch --> PC2 (4k JF) => not OK [needs to fragment message with ping packets > 1514 for example]

3) PC1/2 (4k JF) --> Switch --> Linkstation1 (4k JF) => not OK [needs to fragment message with ping packets > 1514 for example]

4) Linkstation1 (4k JF) --> Switch --> PC1/2 (1514 bytes) => not OK [ping with packets > 1514 are timing out]

5) Linkstation1 (4k JF) --> Switch --> PC1/2 (4k JF) => not OK [ping with packets > 1514 are timing out]

Here is an interesting thing I saw in the snoops I took on the PC with Whireshark:
@2) & 3): I never see a packet going out from the PCs NIC.

@4): Whireshark never saw the incoming bigger packet. So the NIC dropped the packet, right?

@5): Whireshark on the PC sees the packet from the Linkstation coming in with the correct bigger size (for example 2000 bytes), but no packet is send out (which results in the timeout on Linkstation side then).

So it seems to me that something inside Windows is not properly set.

Taking 4) & 5) together I could assume the NICs property setting is somehow taken into account on the PC as enabling JF in the NIC let Whireshark see the packet coming into the NIC, but it gets dropped in the later processing in Windows...

Cheers,
Frank

 

[00Roush]

As a sanity check I just tested jumbo frames between my main computer and my home server. Both have Marvell PCIe based network cards. It seemed to work just fine. Used Microsoft Network Monitor to confirm packet sizes were 9014. Also tested the same ping command you are trying to use and it worked. My guess your problem is a software problem somewhere. Maybe a program you are using currently or used in the past messed up some of the network settings. Just a guess.

Completely uninstalling and then reinstalling the network driver might help but you already mentioned the driver upgrade so maybe not. Uninstalling any software that has to do with the network might also help. (ie firewalls or programs like TCPoptimizer) Updating windows to the latest service pack. You probably have already tried all of this but just want to double check. Last on the list would most likely be a windows reinstall but that might be out of the question.

00Roush

 

[frankomat]

Hi 00Roush,

I started now to scan my PCs for malware, viruses, rootkits, ... nothing so far.
The next step will be to remove the firewall and the antivirus software.
I guess also that some software is blocking JF.

Anyhow, I booted from a Ubuntu 9.04 LiveCD on one of the PCs and was able to set the MTU to 4k just by calling ifconfig.
=> 35 MB/s read via FTP from the Linkstation!
Without JF it's 20MB/s... so it works and the hardware is not the issue.

Cheers,
Frankomat

 

[00Roush]

Well glad to see it works in Ubuntu. I hope it isn't malware or virus. Let us know how it works out.

Almost forgot... you should see if reloading the network stack helps. Here's the Microsoft link that describes the process. http://support.microsoft.com/kb/299357

00Roush